Method of placing and driving concrete piles.



J. STEWART.

METHOD OF PLACING AND DRIVING CONCRETE PILES. APPLICATION FILED JAN.28,I914.

1,157,444. 7 Patented Oct. 19, 1915.

7 i16666.' Jam, 53611941 5;

UNITED STATES; PATENT oFrIcE.

JOHN STEWART, OF NORWOOD, OHIO. ASSIGNOB TO THE SIMPLEX CONCRETE PILINGCOMPANY, OF 'WASHING'ION, DISTRICT DISTRICT OF COLUMBIA.

OF COLUMBIA; A CORPORATION OF THE METHOD OF PLACING AND DRIVING CONCRETESpecification of Letters Patent.

Patented Oct. 19, 1915.

Application filed January 28, 1914. Serial No. 814,892.;

T all whom it may concern:

Be it known that I, JOHN S'rswaa'r, a citizen of the United States,residing in Norwood, county of Hamilton, State of Ohio, have inventedcertain Improvements in the Methods of Placin and Driving ConcretePiles, of which the ollowing is a specitication.

The object of my invention is to improve the method of drivingpre-molded concrete piles so as to prevent the disintegration of thepile during the driving process and to economize in the time necessaryto drive the ile.

p In the accompanying drawings: Figure 1 is a view illustrating a pileform driven in the ground to make a hole for the reception of the moldedconcrete pile; Fig. 2 is a sectional view showing the character of ahole after the form has been removed; said hole containing grout in thebottom; Fig. 3 is a sectional view showing the pre-mol ed concrete pileinserted in the hole; and Fig. 4 is a sectional view showing thepre-mplded concrete pile driven to its fina position; the grout fillinthe voids between the walls of the hole an the pile.

A pre-molded concrete pile, z. e., a pile which has been cast first andallowed to cure from thirty to sixty days, is difficult to drive intosome soils under certain conditions. Under ordinary conditions thepremolded pile is placed in the pile driver leads and is sunk by drivingwith a drop or steam hammer in the same manner as wooden piles aredriven. When long piles of this character are re aired to reach aconsiderable depth, the riction of the earth is so great thereon as tomake the driving difiicult and it frequently happens that the value ofthe pile is destroyed during the process of driving. By my improvedmethod, the pile can be driven to its full depth without clan er ofbeing fractured or disintegrated an the voids in the ground surroundingthe pile are filled by the material used in aiding the pile to penetratethe earth.

Referring to the drawings, 1 is the ground into which the pile is to bedriven.

2 is the removable preparatory pile having a casing 3 and a oint 4. Inthe resent instance, this point 4: is of a greater diameter than thecasing 3 formin the body of the pile, consequently, the ha y portion isfreed from frictional contact with the walls of the opening; thusfacilitating the driving of the preparatory form and the withdrawal ofthe same when it has reached the proper de th.

n the resent instance, the body portion consists o a metal tube,although it may be made of wood or solid metal, if desired, with adriving head 5 at) the top. The point 4 extends into the casing and istapered, as shown, so as to displace the earth laterally as it entersthe ground. This preparatory pile is driven into the ground by anysuitable means to a depth less than the full dc th required for t efinished pro-molded pi e, leavin five or six feet of ground to bedisplaced in driving the pre-mo (led pile. After the preparatory pilehas beendriven to the desired depth, it is withdrawn, leaving a hole inthe round. The 'hole,'in some instances, may be irregular, as shown inthe drawings, due to the movement of the earth. I pour into the hole aquantity of very wet cement grout, which acts as a lubricant to assistin driving the pro-molded concrete pile. The pre-molded concrete pile 6is then lowered into the hole, as illustrated in Fig. 3, and is drivenby means of a drop or steam hammer to its final penetration, asillustrated in Fig. 4. The grout, as stated above, assists in thelubrication of the pile and, as the pile is driven, this grout worksitself into the space between the rough walls of the hole and the pile;filling any voids which may have formed. \Vhen this cement grout setsand hardens. the voids are filled with solid material, making anexceedingly substantial and satisfactory pile.

In driving the pro-molded concrete pile the short distance necessary, itis not injured to the same extent as where it is driven the fulldistance by the drop or steam hammer. In some instances, instead ofgrout, I may use water, where the voids in the earth are comparativelysmall, but I prefer to use grout in most cases.

I preferably make the hole for the premolded pile of a greater diameterthan the pile, although it may be of the same diameter or even of asmaller size than the pile, in which case it will be understood that itis necessary to drive the pro-molded pile into the hole.

(r in the present instance, about In some character of ground, the holewill be substantially the same diameter as the preparatory pile, but inother character of ground the walls may form an irregular opening, asshown in Fig.2, or, if the ground is very soft, the hole made by thepreparatory pile may be entirely closed, but even should the hole beclosed, .it will be much easier to drive the preparatory concrete pileinto the ground than if the pile made the initial penetration.

In extremely hard ground the hole made by the preparatory pile may bethe full length of the pre-molded concrete pile and the grout is placedin the hole to lubricate the concrete pile and to fill any voids aroundthe pile. p

In some instances it may be possible to place the pre-molded concretepile in the hole and to allow it tov sink-by its own weight, in place ofsinking it by driving, if the hole is made rather large and the groundin which the hole is made is sufficiently hard and firm to keep thelarge diameter hole intact. Y

It will be understood that the pre-molded concrete pile can be madesolid, hollow, or may be reinforced to any extent desired. Thereinforcing will depend considerably upon the length and the diameter ofthepile, and while I have shown a round pile, it may be hexagonal or inany other shape desired to efliciently perform the function for which itis intended.

My invention relates solely to the method of placing the pile into theground.

I claim:

1. The method herein described of driving a pre-molded concrete pileinto the ground,

said method consisting-in first making a hole by driving a preparatorypile to a depth less than the full depth to which the concrete pile isto be driven; removing the preparatory pile; inserting a quantity ofcement grout into the hole;.and driving a pre-molded concrete pile inthe hole to a depth greater than the preparatory pile was driven.

2. The method herein described, of driving pro-molded concrete piles inthe ground; said method consisting in first making a hole by driving apreparatory pile to a depth less than the full depth of the concretepile to be driven; inserting in the hole a quantity of grout in a liquidstate; then placing a premolded concrete pile in the hole and driving itto the depth required; the grout forming a lubricant for the pre-moldedconcrete pile as it is driven and filling the voids formed .be-

tween the walls of the hole and the concrete pile; the concrete, when itsets, forming a solid mass which enters the voids.

In testimony whereof, I have signed my name to this specification, inthe presence of two subscribing witnesses.

JOHN STEWART.

Witnesses:

JEANNETTE STEINMETZ, LoUIs R. How.

